U.S. Pat. No. 4,732,588, issued May 22, 1988 and assigned to the assignee of this invention describes a motor vehicle fuel vapor storage and recovery apparatus including a fuel vapor storage canister, an atmospheric vent port on the storage canister, a body of fuel vapor adsorbent material such as activated carbon granules in the canister, a vapor conduit, a purge conduit, and a thermoelectric cooler/heater. A fuel vapor/air mixture is expelled from a fuel tank of the motor vehicle and conducted to the vapor storage canister through the vapor conduit where it circulates through the body of adsorbent material toward the atmospheric vent port. The fuel vapor fraction of the fuel vapor/air mixture adsorbs in the pores of the adsorbent material while the air fraction of the mixture escapes through the atmospheric vent port. The purge conduit is connected to the vapor storage canister and to a source of vacuum such as an intake manifold of an internal combustion engine. When the vapor conduit is closed by a control valve, a pressure gradient between the atmosphere and the intake manifold induces a flow of air into the vapor storage canister through the vent port. The in-flowing air desorbs the fuel from the pores of the adsorbent material and the resulting fuel vapor/air mixture is purged from the vapor storage canister through the purge duct and consumed in the engine. Fuel vapor adsorption and desorption are analogous to condensation and vaporization. Accordingly, adsorbed vapor will be referred to herein as liquid fuel in the pores of the adsorbent material. The thermoelectric cooler/heater cools the vapor conduit to promote condensation of fuel vapor from the fuel tank and heats the body of adsorbent material to promote vaporization of the liquid fuel therefrom. Purging by vacuum into an internal combustion engine complicates control of the engine because the concentration of fuel vapor in the purged fuel vapor/air mixture varies. When the propulsion system of the motor vehicle includes a fuel cell, successfully vacuum purging a fuel vapor/air mixture into the fuel cell fuel stream is difficult because the variable concentration of fuel vapor in the fuel vapor/air mixture adversely affects the operation of certain fuel cell components. A fuel vapor storage and recovery apparatus and method according to this invention is a novel alternative to the vapor storage and recovery apparatus described in the aforesaid U.S. Pat. No. 4,732,588.